The invention involves a compress gas container constructed of an Austenite steel alloy which is provided in particular for storage and distribution of gases. Those installations and devices employed for storage and distribution of ultra-pure gases, which e.g. are being used increasingly in the semi-conductor industry, are required to fulfill ever more specialized requirements. Thus, only those materials may be used, the surfaces of which can be pre-treated so that the pure chemical composition of the gases which come into contact with them will not change. Especially, there must be no emission of surface particles such as would contaminate the gases in an inadmissible manner.
These prerequisites can no longer be met by the traditional ferritic constructional materials. Therefore, all the component parts presently used for storing and distributing ultra-pure gases are manufactured of Austenite CrNi steels, and their surfaces in contact with the gases are "polished" electrolytically. By electrolytic polishing, the surface layer that has been contaminated and covered by the manufacturing and finishing processes especially, is eliminated. In addition, the surface roughnesses are smoothed out, and thus the surface area lessened which effectively comes in contact with the medium.
Whereas this technology is already in widespread use in the case of containers for transporting and storing supercooled liquid gases, still there exist formidable, as yet unsolved difficulties in the matter of transferring these methods to compress gas containers for compressed ultra-pure gases.
The chief obstacle is presented by the extraordinarily low mechanical ductility of the Austenite steels. Compared to the usual ferritic pressure container materials, Austenite CrNi steels, if made of use in the ordinary commercial fashion, will exhibit characteristic values for toughness that are diminished by a factor of from 3 to 4. In the case of containers of equal capacity, this would signify a correspondingly larger outlay of building material and a correspondingly heavier weight. The result would be that the storage space, as related to the overall weight, of such traditionally-used Austenite compress gas containers would reduce to insignificance. Therefore, their use in the transporting of gas, e.g. as compress gas flasks, is arguably economical only in exceptional cases.